I'm starting a cut cycle and am wondering if eating watermelon would be bad while trying to cut. Does anyone know? I would assume it wouldnt be great cause of the sugar but wasn't sure.

Eating fruit/sugar and carbohydrates is NOT bad if you're trying to lose fat. In fact, you NEED some. I highly recommend that you read The 3 Keys to Fat Loss - it lays everything out re nutrition and training for the beginner and experienced trainee.